绵羊痘病毒ORF121基因的序列分析及其B细胞表位预测

Analysis and prediction of the B cell epitopes of ORF121 gene from Sheeppox virus

选取GenBank上4株不同绵羊痘毒株ORF121基因序列，采用DNASTAR软件对该基因序列进行同源性分析，并以B细胞表位分析参数及蛋白质二级结构分析数据，综合预测ORF121蛋白B细胞表位。结果表明：4株不同绵羊痘毒株ORF121基因核苷酸序列的同源性为99％；在ORF121蛋白的肽链中，35～46、76～82、160～167区段亲水性强，35～45、54～83、90～124、130～139、144～158和160～167区段柔韧性好，37～45、112～116、129～137和143～167区段抗原指数高，33～45、78～83和159～167区段表面可及性高，30～57和151～170区段可形成一定的空间构象。结果说明ORF121基因在不同的绵羊痘病毒流行株之间非常保守，ORF121蛋白35～45、160～167区段可能是B细胞表位优势区，具有潜在的疫苗或／和诊断价值。

Four different ORF121 glycoprotein genes of the sheeppox virus strains were selected from GenBank to analysis their identity by the DNASTAR software, and the B cell epitopes of ORF121 glycoprotein were predicted based on the analysis parameters of B cell epitopes and the characteristic of the secondary structure. The ORF121 glycoprotein genes of four strains share 99 % homology at nucleotide level, and there are a stronger hydrophilicity in the regions 35～46,76～82 and 160 ～ 167, and a better flexility in 35 ～45,54 ～83,90 ～ 124,130～ 139,144 ～158 and 160 ～ 167, and a higher antigenic index in 37 ～ 45,112 ～ 116,129 ～ 137 and 143～167, a finer surface probability in 33 ～ 45,78 83 and 159 ～ 167, and a spatial structure predominance in 30 ～57 and 151 ～ 170, Together with above results suggest that the ORF121 gene is completely conserved among sheeppox field strains, it probably has the B cell epitopes in the regions 35 - 45 and 160 - 167, and ORF121 glyeoprotein has potential value of vaccine or/and diagnosis.